Instructions

• Preheat the oven to 350°F. Line a 9x13-inch baking pan with heavy‑duty aluminum foil, leaving at least a 2‑inch overhang on two opposite sides, and spray the foil lightly with nonstick baking spray. Set the pan aside.
• In a large bowl, combine the crushed Oreo crumbs and the melted butter; stir until the crumbs are evenly moistened.
• Press the crumb mixture firmly into the bottom of the prepared pan and slightly up the sides. Bake the crust at 350°F for 10 minutes. Remove from the oven and transfer the pan to a wire rack to cool. Reduce the oven temperature to 325°F.
• Set up a double boiler: fill a medium pot about one‑third full with water and bring it to a low simmer over medium heat. Place a heatproof bowl on top of the pot so the bottom of the bowl does not touch the water.
• Put the 12 ounces coarsely chopped bittersweet chocolate into the bowl and reduce the heat to low. Stir occasionally until the chocolate is completely melted. Remove the pot from the heat and leave the bowl on top of the pot while you make the filling; set aside.
• In the bowl of a food processor (or a mixer), pulse the room‑temperature cream cheese until smooth, scraping down the sides as needed (about 2 minutes).
• Add the granulated sugar, packed light brown sugar, and unsweetened cocoa powder to the cream cheese and process/beat until smooth and fully combined.
• With the mixer on low, add the 4 large eggs and 2 large egg yolks and the 1 cup room‑temperature heavy cream. Mix just until combined (about 20 seconds).
• Using a silicone spatula, fold the melted bittersweet chocolate into the cream cheese mixture until evenly incorporated. Fold in the 2 teaspoons vanilla extract. Remove the bowl from the processor and stir the filling a few times with the spatula to ensure even blending.
• Scrape the filling over the partially baked crust and smooth the top. Bake at 325°F for about 35 minutes, or until the center is set but still slightly jiggly. The cheesecake will finish setting as it cools.
• Remove the pan from the oven and place it on a wire rack. Carefully loosen the foil from the pan edges, then run the tip of a knife around the inside edge of the pan to release the cheesecake. Allow the cheesecake to cool completely in the pan on the rack.
• Once cooled to room temperature, transfer the pan to the refrigerator and chill for at least 4 hours (or until fully chilled) before removing from the pan and slicing.
• To make the ganache, place the 16 ounces finely chopped semi‑sweet chocolate in a large heatproof bowl.
• In a small saucepan over medium heat, bring 1 1/4 cups heavy cream to a rolling simmer, then immediately remove from the heat. Pour the hot cream over the chopped semi‑sweet chocolate and let sit for 1 minute. Whisk until the mixture is smooth and glossy.
• Let the ganache cool until tepid. Spoon approximately 3/4 cup of the ganache into a large piping bag fitted with an open star tip and set the bag aside.
• Pour the remaining ganache over the chilled cheesecake and spread evenly. Let the ganache set at room temperature for about 1 hour, or until firm.
• Use the foil overhang to lift the cheesecake from the pan and transfer to a cutting board. Using a thin‑bladed sharp knife, slice into bars, wiping the knife clean between each cut.
• Pipe a star of the reserved ganache onto each bar. Serve immediately, or store loosely covered in the refrigerator for up to 5 days.